一种RBAC改进模型及其在军事Web信息系统中的应用

军事Web信息系统要求用户权限必须严格控制、统一管理、维护简便.基于RBAC的访问控制模型能有效弥补DAC和MAC的不足.针对著名的RBAC96模型的缺陷,提出数据资源以业务功能表示、预设角色与用户临时权限的改进角色权限控制模型.该改进方法已经在某军事Web信息系统中得到了应用.     

Fibroblast protein profile analysis highlights the role of oxidative stress and vitamin K recycling in the pathogenesis of pseudoxanthoma elasticum

Pseudoxanthoma elasticum (PXE) is a genetic disorder associated to mutations in the ABCC6 gene; however, the pathogenetic mechanisms leading to elastic fibre calcifications and to clinical manifestations are still unknown. Dermal fibroblasts, directly involved in the production of the extracellular milieu, have been isolated from healthy subjects and from patients affected by PXE, cultured in vitro and characterized for their ability to produce reactive oxygen species, for structural and functional properties of their cell membranes, for changes in their protein profile. Data demonstrate that oxidative stress has profound and endurable consequences on PXE fibroblast phenotype being responsible for: reduced levels of global DNA methylation, increased amount of carbonylated proteins and of lipid peroxidation products, altered structural properties of cell membranes, modified protein expression. Data shed new light on the pathogenetic pathways in PXE, by identifying a network of proteins affecting elastic fibre calcification through inefficient vitamin K recycling, and highlight the role of differentially expressed proteins as targets for validating the efficacy of future therapeutic strategies aiming to delay and/or revert the pathologic phenotype of PXE fibroblasts. Moreover, data open new perspectives for investigating PXE-like phenotypes in the absence of ABCC6 mutations.     

Proteomics identification of differentially expressed proteins in the muscle of dysferlin myopathy patients

The muscular dystrophies are a large and heterogeneous group of neuromuscular disorders that can be classified according to the mode of inheritance, the clinical phenotype and the molecular defect. To better understand the pathological mechanisms of dysferlin myopathy we compared the protein-expression pattern in the muscle biopsies of six patients with this disease with six patients with limb girdle muscular dystrophy 2A, five with facioscapulohumeral dystrophy and six normal control subjects. To investigate differences in the expression levels of skeletal muscle proteins we used 2-DE and MS. Western blot or immunohistochemistry confirmed relevant results. The study showed specific increase expression of proteins involved in fast-to-slow fiber type conversion (ankyrin repeat protein 2), type I predominance (phosphorylated forms of slow troponin T), sarcomere stabilization (actinin-associated LIM protein), protein ubiquitination (TRIM 72) and skeletal muscle differentiation (Rho-GDP-dissociation inhibitor ly-GDI) in dysferlin myopathy. As anticipated, we also found differential expression of proteins common to all the muscular dystrophies studied. This comparative proteomic analysis suggests that in dysferlin myopathy (i) the type I fiber predominance is an active process of fiber type conversion rather than a selective loss of type II fibers and (ii) the dysregulation of proteins involved in muscle differentiation further confirms the role of dysferlin in this process.     

A mechanical comparison of high-flexion and conventional total knee arthroplasty

The question addressed in this study was whether high-flexion total knee arthroplasty (TKA) designs improve the mechanical behaviour of TKAs in high flexion and whether they maintain the mechanical performance of conventional TKAs at normal flexion angles. A finite element study was performed in which the mechanical behaviour of the conventional Sigma RP and the new high-flexion Sigma RP-F were compared, during a dynamic simulation of a high-flexion squatting activity. Forces, stresses, and contact positions were calculated during different stages of the simulations. In general, higher stresses were found with larger flexion angles for both designs. Mechanical parameters were similar in normal flexion. In high flexion, lower stress and deformation values were found for the high-flexion Sigma RP-F, except for the contact stress at the post of the insert. This study confirms that a high-flexion design can improve mechanical behaviour at high-flexion without changing the performance in normal flexion. Hence, although a high-flexion TKA may show a similar or better performance in comparison with a conventional TKA, high-flexion activities still cause an increase in the implant stress levels. Therefore, the patient's demand for large flexion angles may reduce the longevity of TKA implants.     

基于可拓学的网络安全报警分析技术研究*

用户的网络管理需要建立一种新型的综合网络安全管理解决方案,即统一网络安全管理。特别关注于其中的一个关键功能——报警分析。其思路是以IDS报警为中心,将报警分析过程分解为包含报警评估与报警相关的两级关联分析模式。为了有效克服现今IDS报警分析技术中存在的问题和局限,顺应网络安全管理的统一化趋势,引入在解决矛盾问题方面极具优势的可拓学,以保证网络安全报警分析各种功能在技术上的实现。     

一种新的海洛因毒源判别方法及其软件使用

应用气质联用(GC/MS)分析方法,获得云南省9个地区缴获的1148个海洛因毒品样品中海洛因、单乙酰吗啡和乙酰可待因3种组分(记为A、B、c)的含量.在对数据做了一维、三维分布情况观察之后,提出一种"等高图"毒源判别模式.建成以地区归属的毒品数据库,并绘制分别用组分A、B、C为Z轴表示的各地区等高图.选择有毒源代表性的5个边境地区的15个等高图基础模式,编制出判别未知样品的毒源鉴定程序软件.对软件的使用过程、判别能力、升级没想也作了说明.     

间歇精馏分离乙醇-DEM体系的研究

为除去DEM粗产品中的少量乙醇,获得高纯度DEM产品,测定乙醇-DEM体系的汽液平衡数据,采用间歇精馏法将体系分离精制.确定了精馏工艺条件,考查了原料组成、填料高度等因素对分离的影响,采用理论板数n≥28的填料蒸馏塔,当原料中乙醇含量等于2%时,产品DEM纯度町高于99.6%,回收率超过88%.为以后的工业装置设计及工业化生产提供了充足的实验依据.     

化工生产过程数据挖掘系统的研究与应用

提出了化工生产过程数据挖掘系统的技术架构,在此基础上,采用多支持度关联规则挖掘算法,开发了化工生产过程数据挖掘软件ESP-Miner,该软件提供OPt Server标准接口,主流实时数据库接口、关系数据库接口ODBC、标准文本格式接口,可集成DCS、实时数据库系统、关系数据库系统及其他系统的生产数据.同时提供人工录入接口集成散点数据.该系统已经在三唑磷合成过程中得到了成功的应用,三唑磷收率提高了1.5%,三唑磷含量从80%提高到了83%,为企业带来了较好的经济效益和社会效益.     

基于直线和单特征点的移动机器人视觉推算定位法

提出了一种基于直线和单特征点的视觉推算定位方法．将摄像机固定安装在移动机器人上,并使摄像机的方向垂直于天花板．提取天花板图像中的两条相交直线及其交点作为特征,利用直线的方向估计机器人的方位,再结合相交点的像素坐标变化量推算出机器人的位置．机器人运动过程中,用作特征的交点接近图像边缘时,更换新的交点作为特征点．室内定位实验结果验证了该方法的有效性．     

基于Web2.0的《网络技术与实践》课程网站的设计与实现

随着计算机网络的发展,网页上的交互性大大增强,本文基于ASP.NET2.0设计实现了<网络技术与实践>的网络课程网站,培养了学生的自主学习能力和创新精神,加强了师生互动.其中的在线实验室24小时开放,学生在校园内随时随地在校园任何一个地方都可以通过校园网络登录在线实验室,进行组网技术的学习.